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PIX performance


I have a pix firewall that protects servers from the internet. Each server has local ip address that is staticly mapped on he PIX to Internet address.

I wonder if PIX performance improves if I assign real ip addresses to the servers ?


  • Other Security Subjects

Re: PIX performance

No I am pretty sure it doesn't, and if it did it wouldn't be noticable. The main reason is that with or without NAT, the PIX performs the same steps. It always checks the translation rules first (even with nat 0), then it checks the permissions (i.e. if there is an access-list and if the packet passes). The PIX ASA always checks translation rules first (and nat 0 is considered a translation as well to the PIX). Also, bear in mind the PIX is a specialized appliance designed for NAT and acls.

Are you experiencing performance issues, if yes it most likely is caused by something else (eg interface load or or

This is a good link to help monitor your PIX performance: .

Hope it helps.